SYSTEM AND METHOD TO REGULATE ULTRAFILTRATION

• US 20110077574A1
• Filed: 09/30/2009
• Published: 03/31/2011
• Est. Priority Date: 09/30/2009
• Status: Active Grant

• Current Assignee: Mozarc Medical US LLC
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Warkentin, Dwight H., Sigg, Daniel C., Audet, Sarah Anne, Bennett, Tommy D.
• Granted Patent: US 9,399,091 B2
• Time in Patent Office: Days
• US Class Current: 604/6.01
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/34 Filtering material out of the blood by passing it through a membrane, i.e. hemofiltration or diafiltration
• CPC Class Codes: A61M 1/3403 Regulation parameters
• CPC Class Codes: A61M 1/3406 Physical characteristics of the filtrate, e.g. urea
• CPC Class Codes: A61M 1/341 by measuring the filtrate rate or volume
• CPC Class Codes: A61M 1/36 Other treatment of blood in a by-pass of the natural circulatory system, e.g. temperature adaptation, irradiation ; Extra-corporeal blood circuits
• CPC Class Codes: A61M 1/3669 Electrical impedance measurement of body fluids; transducers specially adapted therefor
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/33 Controlling, regulating or measuring
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3344 Measuring or controlling pressure at the body treatment site
• CPC Class Codes: A61M 2205/3523 using telemetric means
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2205/502 User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 2205/52 with memories providing a history of measured variating parameters of apparatus or patient
• CPC Class Codes: A61M 2230/005 Parameter used as control input for the apparatus
• CPC Class Codes: A61M 2230/04 Heartbeat characteristics, e.g. ECG, blood pressure modulation
• CPC Class Codes: A61M 2230/20 Blood composition characteristics
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 2230/30 Blood pressure A61M2230/04 takes precedence
• CPC Class Codes: A61M 2230/65 : Impedance, e.g. conductivity, capacity

Abstract

A medical device system including a physiological sensor and ultrafiltration unit senses a physiological signal in a patient and computes a fluid status measurement of the patient using the physiological signal. Ultrafiltration therapy is delivered to the patient according to a therapy delivery control parameter established in response to the fluid status measurement.

Claims

1. A medical device system, comprising:

an medical device comprising a sensor sensing a physiological signal in a patient;

a processor configured to receive the physiological signal and compute a fluid status measurement of the patient using the physiological signal;

a therapy delivery device for delivering ultrafiltration therapy to the patient according to a therapy delivery control parameter; and

a controller configured to receive the fluid status measurement and establish a setting for the control parameter in response to the fluid status measurement.

2. The system of claim 1 further comprising a memory storing a target range of the fluid status measurement;

the controller further configured to compare the fluid status measurement to the target range and establish the control parameter in response to the comparison.

3. The system of claim 2 wherein the processor is further configured to determine a trend of previously computed fluid status measurements and compute the target range using the trend.

4. The system of claim 2 wherein the control parameter corresponds to a flow rate and the controller is further configured to establish the control parameter in proportion to a difference between the fluid status measurement and the target range.

5. The system of claim 2 further comprising a memory storing a target level of the fluid status measurement,

the processor, the controller and the ultrafiltration therapy delivery device configured to operate cooperatively to perform ultrafiltration until a current fluid status measurement reaches the target level.

6. The system of claim 1 further comprising a memory storing a therapy delivery threshold;

the processor further configured to compare the fluid status measurement to the therapy delivery threshold and detect a need for ultrafiltration therapy in response to the comparison;

the controller being further configured to enable the ultrafiltration therapy delivery device in response to detecting the need.

7. The system of claim 1 wherein the controller is further configured to receive an updated fluid status measurement during delivery of ultrafiltration therapy and to determine an adjusted setting for the control parameter in response to the updated fluid status measurement.

8. The system of claim 1 wherein the controller is an implantable unit and the controller and the therapy delivery device are configured for wireless communication.

9. The system of claim 1 wherein the implantable medical device further comprises a telemetry module and the processor is an implantable processor implemented in the implantable medical device;

the controller being an external device in bidirectional telemetric communication with the implantable medical device.

10. The system of claim 1 further comprising a memory for logging an ultrafiltration therapy session delivered by the therapy delivery device according to the established control parameter.

11. A method for use in a medical device system comprising a physiological sensor and an ultrafiltration therapy delivery device, the method comprising:

sensing a physiological signal in a patient;

computing a fluid status measurement of the patient using the physiological signal;

delivering ultrafiltration therapy to the patient according to a therapy delivery control parameter; and

establishing a setting for the control parameter in response to the fluid status measurement.

12. The method of claim 11 further comprising:

storing a target range of the fluid status measurement;

comparing the fluid status measurement to the target range; and

establishing the control parameter in response to the comparison.

13. The method of claim 12 further comprising determining a trend of previously computed fluid status measurements and computing the target range using the trend.

14. The method of claim 12 wherein establishing the control parameter comprises establishing a flow rate in proportion to a difference between the fluid status measurement and the target range.

15. The method of claim 12 further comprising storing a target level of the fluid status measurement,

performing ultrafiltration until a current fluid status measurement reaches the target level.

16. The method of claim 11 further comprising storing a therapy delivery threshold;

comparing the fluid status measurement to the therapy delivery threshold and detecting a need for ultrafiltration therapy in response to the comparison;

enabling the ultrafiltration therapy delivery device in response to detecting the need.

17. The method of claim 11 further comprising:

computing an updated fluid status measurement during delivery of ultrafiltration therapy; and

determining an adjusted setting for the control parameter in response to the updated fluid status measurement.

18. A computer readable medium storing a set of instructions which cause a programmable processor implemented in a medical device system comprising a physiological sensor and an ultrafiltration unit for performing a method comprising:

sensing a physiological signal in a patient;

computing a fluid status measurement of the patient using the physiological signal;

delivering ultrafiltration therapy to the patient according to a therapy delivery control parameter; and

establishing a setting for the control parameter in response to the fluid status measurement.

19. The computer readable medium of claim 18 further comprising determining a trend of previously computed fluid status measurements and computing the target range using the trend.